New consecutive photochemical reactions of naphtho[1,8-de]-1,3-dithiin-1-N-tosylsulfilimines via the through space interaction between two sulfur atoms; A convenient method for preparation of N-tosylaldimines

Naphtho[1,8-de]-1,3-dithiin-1-N-tosylsulfilimines underwent facile consecutive photochemical reactions to give quantitatively the corresponding N-tosylaldimines, together with naphtho[1,8-cd]-1,2-dithiole, via a sulfur-sulfur interaction. The intermediate, 3-hydro-3-phenyl-naphtho[1,8-e][1,4]dithia[2]-azepin, was isolated by liquid chromatography of the reaction mixtures, and its structure was determined by X-ray crystallographic analysis. The proposed mechanism for these photochemical reactions is based on quantum yield measurements, photo-intensity effects, and crossover experiments. (C) 1998 John Wiley & Sons, Inc.